I've got and old Azuki that I plan to replace the bottom bracket and crank set on. Eventually converting to a Fixed gear. The frame is from the early 70s I believe. Serial Number: 74 12 13655.
I'm not entirely sure what type of bearings are on there now but I would like to replace them with a sealed bearing cartridge style.
I'm just trying to figure out what size to buy. I've got most of it figured out. The crank set I will be using is a Sugino with a Square tapper. I'm pretty sure that the frame has the English (I.S.O.) Threading. It seems that there are two measurements that I have to worry about. One of which I'm pretty sure is the 68mm The other is what I'm not so sure about, which I think is spindle width. From what I understand the factors for this measurement depend on the crank set that you plan to use as well as the CHAINLINE
(since it will be a fixed gear there will be high chain tension, so I'm guessing that I'm going to want the CHAINLINE to be pretty staight).
I just need to know if it has anything to do with the width of the Bottom Bracket "tube" of the frame. Or if there are any other factors to take into consideration.